Krivoy W A, Couch J R, Stewart J M
Psychoneuroendocrinology. 1985;10(1):103-8. doi: 10.1016/0306-4530(85)90044-7.
Synaptic modulation refers to altered excitability of a synapse by a substance that does not produce a spike potential at the synapse. Available evidence points to the conclusion that beta-melanocyte stimulating hormone (beta-MSH) modulates synaptic transmission through monosynaptic pathways in the cat spinal cord. Earlier evidence is reviewed, and new data are presented. In the first experiments populations of cells contributing to a knee jerk were studied using the Lloyd preparation, and MSH was found to increase the monosynaptic reflex. With intracellular single unit recording techniques, beta-MSH was found to facilitate recovery from synaptic transmission. With extracellular single unit recording techniques and iontophoretic methods for drug application, beta-MSH has been found to increase the probability of generation of single spike potentials by alpha-motoneurons in response to orthodromic stimulation. Administration of beta-MSH did not cause spontaneous discharge of alpha-motoneurons. The physiological and pharmacological importance of synaptic modulation is discussed.
突触调制是指突触的兴奋性被一种在突触处不产生动作电位的物质所改变。现有证据表明，β-黑素细胞刺激激素（β-MSH）通过猫脊髓中的单突触通路调节突触传递。本文回顾了早期证据并给出了新数据。在最初的实验中，使用劳埃德标本研究了参与膝跳反射的细胞群，发现MSH可增强单突触反射。采用细胞内单单位记录技术，发现β-MSH有助于突触传递的恢复。采用细胞外单单位记录技术和离子电泳给药方法，发现β-MSH可增加α运动神经元在接受顺向刺激时产生单个动作电位的概率。给予β-MSH不会引起α运动神经元的自发放电。本文还讨论了突触调制的生理和药理重要性。
